How does Balram believe that he is living like a man (I just need a few bullet points notes of what I should talk about in this intro and a quote to back it up). How is his behavior immoral (same thing)?

How does Balram believe that he is living like a man?
For Balram, "living like a man" means to live freely and be in control of one's own direction in life. This can be summarized by the following statement regarding his murder of Mr. Ashok:

Yet...even if they throw me in jail...I'll say it was all worthwhile to know, just for a day, just for an hour, just for a minute, what it means not to be a servant.


Balram's father—Vikram, Balram's father, is a poor rickshaw driver. His ambition for his son is that one day he will complete his education and live like a man. This is what first plants the idea in Balram's mind. As his father is not an example of somebody living like a man, Balram looks to Vijay, a bus driver and politician who began as a pig farmer's son. According to rumors, Vijay ascended socially after sleeping with another politician, but Balram doesn't care. This foreshadows Balram's own crime (murdering Mr. Ashok). He learns from Vijay's example that a person must do whatever is necessary to rise above what he or she was born into.

The Animals—The Animals are the four wealthy landlords who take advantage of Balram and his fellow villagers. They are personifications of everything preventing Balram from living like a man and controlling his own destiny. They harass the villagers and impose ridiculous taxes, serving as an example of Balram's notion of the "eat or be eaten" social context in India. With such cruel figures acting as gatekeepers to Balram's agency, it is almost inevitable that he will have to do something extreme to break free and take control of his own life.

Balram's nightmares—Interestingly, Balram does not experience guilty nightmares about his crime. Rather, his nightmares are that he never murdered Mr. Ashok at all. To him, the most terrifying thought is that he remained stuck in poverty his entire life, and was unable to "live like a man."
How is Balram's behavior immoral?
The difficulty with judging the morality of any action is that a moral baseline has to be established first. In most contexts, Balram's murder of Mr. Ashok would be considered immoral. Many societies judge murder among the most serious of crimes. Balram, however, does not necessarily view his action as immoral, and believes that it was necessary for him to live as his own master and take charge of his life. In order to understand this, it is necessary to understand the social context Balram experiences in India - both its historical caste system, which segregated people into thousands of categories and roles, and Balram's assertion that India has outgrown a traditional moral framework. 
According to Balram, the caste system organized India like a zoo; each caste had its own place, and movement among the castes was impossible. Everybody was locked in his or her own cage. The abolition of the caste system, he argued, did not accomplish much for equality. Rather, it turned India into a jungle, with predators and prey. Each participant in society either became a slave or enslaved others, as all prescribed roles had been taken away. In this context, an action like murder is almost a necessity in order to advance and break out of the place a person is born into.
Contrast Balram's understanding of his situation with his grandmother's - she is short-sighted, sending the family's children to work before they can complete school, which prevents them from ever breaking out of their social enslavement. Late in the story, Balram expresses his intention to open a school, so he obviously understands the importance of education. Unlike his grandmother, he understands that a good education could help somebody born in his social context to break free, even though he did not use education to liberate himself. 
Despite all of this, however, he does not regret murdering Mr. Ashok, stealing his money, and using those actions as the catalyst for his own escape from poverty. It's hard to judge whether or not Balram acted immorally. He murdered somebody opportunistically, but he isn't a "bad" person through and through. Regardless of the action's morality, it is soundly established that Balram does not regret what he did.